问存储过程错误算术溢出将numeric转换为数据类型varchar时出错

EN

USE [Sost_Dev]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

ALTER PROCEDURE [sost].[GetExternalOrderNumbers]
    @Count int
AS
BEGIN
    SET NOCOUNT ON;
DECLARE @year VARCHAR(2)
DECLARE @ExternalOrderNumbers nvarchar(50)

SET @year = RIGHT(CAST(DATEPART(yy, GETUTCDATE()) AS VARCHAR(4)),2)

    -- Insert statements for procedure here
BEGIN TRAN
SAVE TRAN seq

            --Creating Temp Table for every isolated connection
            CREATE TABLE #NewOrders(ExtOrderNumber nvarchar(50));

            WHILE @Count > 0
                BEGIN
                   INSERT INTO [sost].ServiceOrderNumberSequence DEFAULT VALUES
                    SET @ExternalOrderNumbers = 'ESON' + @year + RIGHT(REPLICATE('0',10) + CAST(SCOPE_IDENTITY() AS  NVARCHAR(7)) ,7);
                    print 'External' + @ExternalOrderNumbers;
                    --Insert New Order Number to Temporary Tables
                   INSERT INTO #NewOrders  values(@ExternalOrderNumbers)
                   SET @Count -=1
                END

COMMIT

--Fetching Order Numbers from Temporary Table.

SELECT @ExternalOrderNumbers as ExternalOrderNumber from #NewOrders
END